I am an atmospheric scientist who specializes in the dynamics of climate and weather, particularly in the tropics, on time scales of days to decades. A major focus of my current research is extreme events – such as hurricanes, tornadoes, floods, and droughts, and the risks these pose to human society in the present and … Continued
My research aims to elucidate fundamental questions about climate such as, What controls the surface temperatures and winds? What shapes rainfall patterns? Where and when do clouds form in the atmosphere? To answer such questions, my group analyzes observational data and performs systematic studies with numerical models, with which we simulate flows ranging from the … Continued
We study air trapped in bubbles in glacial ice to understand the mechanism of Earth’s climate system, through the record of past climate contained in ice cores from Antarctica and Greenland. Our group develops novel proxy indicators of past temperature, precipitation, and storminess using atmospheric noble gases and their stable isotopes, and is also using … Continued
My research in the area of organic geochemistry is focused on applications of analytical chemistry, isotope geochemistry, and molecular biology to biochemical oceanography and Earth history. The “how, when, and why” of microbial processes yield insight about environmental conditions on Earth today, in the past, and about potential human impacts on our future. My recent … Continued
I have been fascinated by electron transfer reactions that support bacterial metabolism for many years. Recently, my lab members and I have become interested in understanding how bacteria generate energy when they are growing slowly–doubling once every few days or weeks–the dominate pace of life on the planet, yet one that is poorly understood. One … Continued
My research group focuses on the connection between Earth’s surface processes and the forces below the surface that drive and shape them. Recently, we reexamined how strong the Earth’s mantle is, and ventured into the connection between thermodynamics and fluid dynamics for our planet. The latter is particularly fascinating as it suggests that the thermodynamics … Continued
I am a geochemist who is interested in understanding (1) the origin and evolution of continents, (2) the chemical and physical differentiation of the Earth and other rocky planets, and 3) the chemical exchanges between the Earth’s interior and the ocean-atmosphere system. I take an interdisciplinary approach to investigating these themes by attempting to bring … Continued
I specialize in low-temperature aqueous and radiogenic isotope geochemistry. My group’s research combines fieldwork, laboratory experiments, and modeling to quantify chemical, physical, and biological phenomena that cycle elements and their isotopes at the Earth’s surface. Many activities use isotopes to probe the compositional evolution of the Earth, at timescales spanning the geological to modern-day. Other … Continued
My group uses geochemical techniques to investigate the geological processes that control the evolution of the Earth. These processes operate on a variety of spatial (and time) scales, ranging from the atomic (using chemical diffusion to quantify the growth rate of minerals) to planetary-wide (using chemical parameters to characterize the nature of mantle convection). Over … Continued
My research covers a range of topics in atmospheric chemistry from air quality to climate change. Our group has been a leader in the development of global 3-D models and in the exploitation of satellite data to quantify emissions and transport. We have led NASA aircraft missions in many remote parts of the world to … Continued